Spray gun



FIG. 1 is a perspective view of a spray gun showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is an enlarged top view thereof; and,

FIG. 7 is a bottom view thereof. 

I claim the ornamental design for a spray gun, as shown and described. 